Multiple-mixture die-casting method and machine



A. AKERS Nov. 18, 1930.

MULTIPLE MIXTURE DIE CASTING METHOD AND MACHINE Filed'Aug. 11, 1927 4Sheets-Sheet l A. AKERS Nov. 18, 1930.

MULTIPLE MIXTURE DIE CASTING METHOD AND MACHINE Filed Aug. 11, 1927 4Sheets-Shet 2 1 llll..

Nov. 18, 1930. A. AK ERS 1,781,939

MULTIPLE MIXTURE DIE CASTING METHOD AND MACHINE Filed Aug. 11, 1927 4Sheets-Sheet 3 Nov. 18, 1930. A. AKERS 1,731,939 MULTIPLE MIXTURE DIECASTING METHOD AND MACHINE Filed Aug. 11, 1927" 4 Sheets-Sheet 4 a M MPatented Nov. 18, 1930 UNITED STATES PATENT OFFICE AXEL AKERS, OFCHICAGO, ILLINOIS, ASSIGNOR T QUALITY HARDWARE & MACHINE CORPORATION, OFCHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS MULTIPLE-MIXTUREDIE-CASTING- METHOD AND MACHINE Application filed August 11, 1927 SerialNo. 212,178.

relatively thick body of one metal or mixture and a relatively thinlining or covering of another metal or mixture, although two or morealloys or mixtures may be employed in the production of a compositehearing or other article, such as a body layer of 92 per cent. zinc, 7.5per cent. copper, and 5 per cent. aluminum or miscellaneousmaterials orother metals, and a lining layer of from 50 per cent. to 85 per cent.tin and the balance lead, thereby producing a die casting in which theuse of a great quantity ofsome expensive metalsuch as tin in the wholethickness of the bearinginstead of merely in the lining is obviated, andat the same time produce an economical hearing or other article which ispractical and efficient as to wearing qualities and which-can be quicklyproduced.

'Another object is to provide a novel method and apparatus for producingoil grooves or the like in the bearing, the construction being such thatthegrooves are automatically formed in the'second layer or lining in theoperation of die casting the bearing, the groove-forming device beingautomatically depressed flush with the surface of the small diameter ofthe core and automatically projected for producing the grooves inthe'second layer before the die casting is ejected.

A further object is to provide a die casting machine having two or morefurnaces or melting pots, each having movable ladles or containers forthe metals, alloys or mixtures usedin the die casting, which move to dipand fill the same and are then brought into position simultaneously orotherwise to discharge the contents thereof into the molds successively59 under air or other pressure admitted into the containers to eject thefluid metal from, the containers to inject the fluid metal into the diesunder pressure or otherwise, the space in the die mold being enlarged bymeans of a movable core, having portions of different size or diameteror otherwise for accommodating the layers successively, after which thedie is opened and the casting ejected. A still further object of theinvention'is to provide for the ejection of the air from .within 60. thedie mold in the'casting of the first layer so as to exclude the latterfrom exposure to air and possible oxidation towhich it is readilysusceptible, by sealing all joints or escape openings with the spruce ormetal forced into the same and by enlarging the space to receive thesecond layer, as by means of movement of the core, establishing asubstantial or partial vacuum, thereby insuring proper fusion or unionbetween the first or outer layer and the second or inner layer, whichwould otherwise be seriously interfered with by exposure of the firstlayer to air and oxidation on the exposed surface to which the secondlayer is joined.

Another object of the invention is to provide a die casting machinewhich is automatic in its operation and wl'iichcarries out thesuccessive steps quickly and in sequence for each die casting operation.4

Other objects and advantages of the invention Will be understood byreference to the following specification and accompanying drawings, inwhich I have illustrated a selected embodiment of the invention and inwhich drawings 2 Fig. 1 '"v a side elevation of the businessor mold endof the die casting machine showing the novel construction.

Fig. 2 is a top plan view;

Fig. 3 is a horizontal longitudinal sectional view of the mold withthe-core in position for die casting the first layer. I Fig. 4 is a viewsimilar to Fig. 3, with the partsin position during the die casting ofthe second-layer. x

' Fig. 5 is a sectional view, taken on line 55 of Figure 3, of the moldwith the parts operatively assembled or together in the die casting" ofthe first layer. 1

Fig. 6 is a sectional view taken on line 66 of Figure 3, showing the oilgroove employed with the machine to eject the metals into the mold.

Fig. 9 is a perspective view of an oil groove forming member.

Fig. 10 is an end elevation of a die cast half-bearing produced by themachine, and

Fig. 11 is an inside elevation ,or bottom View of the bearing shown inFigure 10 and illustrating the oil grooves.

Referring to the drawings in detail,11 in-' dicates a table or framesupported onlegs 12, this table being the usual table employed inconnection with die casting machines of the horizontal type, although itis to be understood that the invention is not limited in its applicationto this particular type of machine but may be applied with equalfacility,

so far as the combination of parts and principles involved areconcerned, to machines of the vertical or other type. Mounted in anopening 11 centrally of the table are two or more melting furnaces orpots 13 and 14, heated by electric heating elements or otherwise, asindicated at 15, and having at the top suitable bearings 16. Thefurnaces or pots 13 and 14 may have suitably apertured lugs for boltingthe same to the top of the table 11, as indicated at 17, and thefurnaces taper toward the opposite ends, as shown more particularly inFigure 2 of the drawings. The bearings 16 take a pivot or shaft;

on which the springs are mounted to rest on the shanks 21 which alsoreceive the bolts to insure the proper seating of the ladles against thedie mold and permit adjustment and equalizing of the tension. Theseladles are adapted to dip in the molten metal in the furnaces or pots 13and 14 and are curved on such an are that when they are raised, theywill fill with. the metal through the mouth portions thereof. It is tobe understood that the ladles may be actuated by the mechanism usuallyemployed for raising the pot or ladle modified as described, orotherwise. Communicating with the ladles orcontainers 19 through theopenings 23 by means of hose or pipes 27 and 28 is a control valve 29whichmay be constructed as shown in Figure 8. As illustrated, the valveis of the cylinder or piston type having a cylindrical casing with aninlet 30 at one end and an inlet 31 at the other for air under pressureand having an exhaust.

axially with respect thereto. A piston 35 is movable in thecylinder orcasing 28 and has a reduced, central portion and enlargements 36 at theends, providing an intermediate annular opening 37. This piston isadapted to be actuated by a stem or rod 38 which passes through asuitable packing gland 39 in the 18 on which are pivotally mountedagainst open end of the casing 29 and is preferably endwise movement, asby spacing sleeves or' openings 20 in the-shanks 21 thereof. The ladlesor containers 19 are of hollow formation and are cut on a concavo-convexarc with a hollow containing space 22 having an internally threadedopening 23 communicating with its inner end and having at its outer endan apertured plug or mouth portion 24 adapted to engage suitable inletorifices or recesses -in the die molds, as: will be later described.

The opposite ends of the ladles 19 have the shanks 21 extendeddownwardly beyond their curved portions and connected by a link 25through equalizing springs 21' with a lever 26 :fulcrumed intermediatelyand adapted to be oscillated by a suitable means such as an eccentricroller, or otherwise, as is common in the art, for moving the ladles.ontheir pivots'simultaneously from a normally lowered position to raiseor swing the same upwardly and by engagement of the roller with thelever to momentarily hold the ladles detachablyrengaged with the pistonas indiis connected by a short link 41 to the upper end of a lever 42fulcrumed intermediately at 43 and having the lower end pivoted to oneend of arod 44 extending along the side of the machine and actuated by acam or disk having an adjacent recess and raised portion successivelydisposed on its periphery so that the inlets and-outlets aresuccessively coveredand uncovered to their respective ladles and to holdthe valve in a neutral position during the greater portion of the timewhen the ladles are lowered.

The die mold arranged onthe table over the furnaces and ladles consistsof a stationary section 45 and a movable section 46 properlv formed toconform and produce the article to be die cast, such as a half-bearing,as shown in the drawings. The cavity or space within the mold forreceiving the metal of the die casting is designated at 47. In Figure 5,the sections of the mold are shown together and receiving a core 48,shown for constructional purposes as being formed of. two sections'heldtogether at 49. This core has a large end 50 with a somewhat reducedportion 51 and a still smaller portion 52.

This core is fixed at its outer end to a plate 53 which is laterallyadjustable and secured at 54 to a slide'55 which slides laterally on atrack 56 of a bracket 57 bolted to the table, which serves to guide thecore horizontally. For actuating the core, the latter may be operativelyconnected at its outer end with an arm 58 fixed to a shaft 59-bearing inthe bracket 57 at the side of the table and adapted to be actuated bycams or other means suitably actuated by the mechanism of the machine inproperly. timed relation with the other mechanism for moving the coreinwardly between the sections of the mold and for successively moving orstepping it outwardly in the successive steps of a plurality in the. diecasting operation when two or more metals, alloys or mixtures are forcedor ejected into the mold cavity for producing the articleto be die cast,as will be particularly described in connection with a half-roundhearing, although it is to be understood that various other articles maybe made in substantially the same manner.

' The movable section 46 of the die is adapted to be actuated by meansofa slide mechanism 60 actuated by a suitable cam, drum and togglemechanism on the machine and hav ing a stationary part 61 boltedon thetable, or otherwise, and braced by the rod 62. Die blocks or shoes 63are fitted against and secured to the movable and stationary sections 46and 47 and the die block of the movable section has a sleeve 64 to takea plunger 65 with connected plates 66 at the inner end thereof withinthe chamber of the die block, and has push-out pins 67 to engage throughcorresponding openings in the sectiou 46 to eject the article produced:in the machine from the mold. An oil hole forming pin 68 also may beprovided in the section 46 to supplement oil groove forming means, aswill be later described.

.The mouths or orifices leading into the cavity-'48 of the mold andwhich are flared to conform to the mouth portions 24 at the outlet endsof the ladles or containers 19 are designated at 69 and have neckportions 70 with one of which a sprue lock or valve'7l cooperates. Thissprue lock passes through the sprue .72 at the neck part 70 and isadaptedto be actuatedby suitable rack and pinion or other mechanismcommon in the art for reciprocating the lock or valve which inciden--tally serves to move the sprue v72 along for discharging the latter andsimultaneously acting as a plug or valve to close the cavity andprevent-the passage of metal of the effective fusion or union betweenthe layers of the article such as wouldbe prevented by surface oxidationand the formation of a powder or loose coating on the exposed surface ifit were subject to exposure to air and consequent oxidation. t is alsounderstood that this partial vacuum is sealed by closing of thejointsbetvveen the mold sections or special escape slots or openingsprovided for this purpose, owing to the air and sprue being forced outbetween the joints of the sections of the mold when the metal underpressure is forced into the cavity thereof "during the first step of diecasting operation. Bythis means, the joints between the sections areefi'ectively sealed and the cavity rendered practically air-tight beforethe second layer or lining ofJthe article is formed.

The cavity 47 isadapted to receive the first mixture or layer 73 whenthe core is in theposition shown in Figures 3 and 5, said cavity havingdeeper portions at the ends to produce the end flanges 74 of ahalf-bearing. In this position, the ladies or containers 19 in the pots13 and 14 have been dipped and raised to fill the same with the moltenmetal and to bring the mouth portions 24 thereof against the orifices69,after which, air under pressure or otherwise isadmitted into the ladleto inject the metal into the cavity 47. This is admitted into the potcontaining the first layer mixture only, through the inlet 75 of thevalve 29, invvhich position the piston 35 has beelrshifted to the rightfrom the. position shown in Figure 8 to uncover the outlets I313 4 and 7to displace the portion 51 and the shoulder or lip 76 from the layer 73so that the smaller portion 52 of the core is in alignment with thecavity 47and the first layer 73. In this position, the lip or shoulder76 remains within and seals the space formerly occupied by the largepart 50 of the core 48 at the left-hand end between sections 45 and 46,and the lip orshoulder 7.7 seals the space 78, and the second ladle orcontainer-'19 Within the pot 14, having also been swung against theorifice 69, air is admitted through the .plpe 79 into the valve 29, andthe piston-35,

having been moved to the left to again un-v cover the outlets 33 and 34,air enters the inlet 31fa-nd the pipe 27 through the outlct ifl forejecting the habbitt orother mixture. of

molten metal from the ladle, and allows'air in the other ladle to escapeto the atmosphere through the port 33 and exhaust It is to be understoodthat the pipes 27 and 28 are connected to the inlet openings 23 ot' theladles and that the discharge of the metal is through -'the outletorifices at the mouth portions 24 of the ladles. The cavity beingentirely sealed, oxidation of the ex posed surface of the layer 73 isabsolutely prevented, and during the shifting of the piston 35compressed air in the ladles exhausts through the port 32 to theatmosphere. Obviously, the movement of the piston 35 is in timedrelation to the other mechanism so that the parts are operated'in propersequence. The babbitt or other mixture forming the innerlayerof thearticle die cast by the machine, such as the bearing indicated, is shownat 80. \Vhen this is formed, the die mold is opened while the core hasits smaller portion of di''- ameter opposite the cavity, by movement ofthe movable section 46 with respect to the stationary section 45. Afterthis, the push-out Y pins are operated to displace the casting, the

ladles having been previously lowered and the sprue lock or valve havingbeen retracted or backed up to open the inlet portion of the orifice 69.

Should it be desired to form oil grooves in the bearing, such means maybe providedin the form of a groove forming member or maker 81, shown inFigures 3, 4, 6, 7 and 9.

.This member has four rings 82 at the proper angle and provided withbottom recesses 83,

the ends of which are extended to produce under-cut portions 84 adaptedto receive and retaint-herein an arcnate spring 85, these parts beingfitted in a slot or seat 86 in the reduced portion 52 of the core 50 sothat when the core is in the position shown in Figures 3 and 6, thisgroove-forming member is depressed into the small. portion of the coreflush with the operative surface thereof. \Vhen the die mold is closed,and after the zinc or first layer has been formed, the core is shiftedlaterally to move the small diameter 52 opposite the same as shown inFigure 4. In this position, the spring 85 st-raightens and forces themember 81 out into the recess 78, so that when the inner layer 80 isproduced it will have the grooves 87 therein produced antomatically inthe die casting operation. Incidentally, it will be noted that the rings82 of the groove forming member close the openingwhere the pin 68 ispositioned so as to form the oil hole 88.

This operation is continued for the die casting of each part or article,and it is, of course, to be understood that the shape of the articledetermines the shapeof the concavity in the mold. It also is to beunderstood that the cores may be slid laterally from one or both sidesand that the number of furnaces or pots for the molten metals ormixtures may be increased and that a movable ladle is provided for eachpot. The elements 15, while described as electric heating elements ofresistance wire, can be substituted by other-heating means. In theformation of the oil grooves,

when the core is partly drawn out to permit "the projection of the oilmaker or groove forming member 81 by the spring 85, the die mold isclosed and the bearing or other article is ejected after the mold hasbeen opened, due to the movement of the section 46 away from the section45. This permits the core 48 to be pushed into its original position, asshown in Figure 3, and the closing of the mold section 46 against thesection 45 depresses the groove forming member 81 into the recess of thesmall core portion 52, so that the portion 51 is in posit-ion to permitthe formation ofthe layer73. This operation may be quickly carried on toeconomically produce an article of composite metals or mixtures havingtwo or more layers. The devices may also be applied to standard machinesfor die casting, such as the type illustrated in Figures 1 and 2 withthe novel features applied thereto.

Die casting machines, especially those of the horizontal type to whichthe invention is I shown applied, are usually controlled by a handlever. Such a machine is operated by a belt pulley running at about R.P. M. with a shaft driving pinion meshing with an integral gearresulting in a speed of 9 R. P. M. of drums controlling the operation orabout 6% seconds per cycle of operation. The drums are right andleft-hand due to outer cam arrangements and are bolted together withfitted bolts having a filler between the drums. The sides of the drumsare provided with cam-ways in which disks run, one disk being fastenedon each side of a lever which fulcrums on the end plate of the bed plateof the table and the other end transmits a vertical or downward motionto two levers, one on each side of the first lever, from which motion istransmitted to a toggle. One end of the toggle is fastened to the bedplate fulcrum stand and the other end to the main slide. When the drumsrevolve, the slide moves backward and forward toward and away from thestationary die holder or block. 'After the die mold has been fastened tothe stationary and movable die holder and the drums have been revolvedso that the toggle is in a straight line position, then the metal isforced into the die mold under pressure. While the drum is revolving,the die mold is closed, the metal containers rise into position, thecores are located, and the air pressure turned on automatically, afterwhich the air is released, the containers dropped, the die mold opened,and the casting ejected from the die mold. The sequence of operationwith the present machine is as follows:

First, the hand lever above referred to for controlling the operation,is thrown over to the right, which lifts the pulley brake throwing outthe automatic stop, and throwing in the countershaft clutch (not shown).The

close the die mold by shifting the movable section against thestationary section, after which the .ladles or containers are liftedinto place and air pressure admitted into the zinc or first mixtureladle for forcing the same into the cavity of the die mold. The spruelock then-closes the inlet aperture of the die I mold, after which thecore is moved to dispose its small portion or diameter opposite l5 layeror body of the die casting has been gformed. Air pressure is thenadmitted into the babbitt or second mixture ladle to exit the moltenmetal or mixture and produce the inner layer or lining of the diecasting and the parts are lowered, after which the die is opened byfurther rotation of the drum and the raising of the toggle. The spruelock then backs up and the push-out pins are finally actuated to pushout the casting. This operation is repeated by moving the core in, sothat its largest'diameter is opposite the cavity of the die mold, whichis the first position in the die casting operation. Then the movablesection of the die mold moves up to close the die mold by thestraightening of the toggle.v This operation is quickly carried on andthe ejection of one mixture or metal is almost instantaneously after theother mixture or metal is injected. Obviously, the cavity may beenlarged one or more times to take two or more metals or mixtures,thereby producing a bearing or other article with two or more layers,according to the requirements, though two are usually sufficient. Thenumber of enlargements of the cavity depends upon the number of stepportions which the core has. While I have shown a' core which is movablelaterally, it isto be understood that it may be moved in any otherdirection than horizontally and thatthe enlargement of the cavity may beproduced in any other suitable manner.

While I have shownand described my invention in a preferred form, I amaware that various chaggis and modifications may be made therein thoutdeparting from the principles of the nvention, the scope of which maybe'determined by reference to the appended claims.

I claim as my inventioni v 1. A die casting machine having a pluralityof melting furnaces, each having movable metal containers to injectfluid metal into a die under, pressure. 2. A die casting machine havinga plurality of melting furnaces, each having movable metal containers, amold having a'cavity with means for enlarging the same, the 65containersbeing adapted to be moved'and drums revolve to straighten thetoggle and the cavity in the die mold in which thefirst.

brought into position to inject different fluid metals from the furnacesinto the-cavity under pressure, and means for actuating said containers.

3. A die casting machine having a plurality of melting furnaces, eachhaving movable metal containers, a mold having a cavwhich are sealed bythe metal upon the injection from the first container to expel air fromthe mold cavity whereby to establish a partial vacuum within the cavityand prevent oxidation of the exposed surface of the metal upon theenlargement of the cavity and .the proper fusion of the second metaltherewith.

4. In a die casting machine, a plurality of melting furnaces, movableladles in each furnace adapted to dip. in the metal thereof for fillingthe ladles at their free ends, and means for ejecting saidmetalsindependently.

5. In a die casting machine, a plurality of melting furnaces, movable laes in each furnace adapted to dip in the metal thereof for filling theladles at their free ends, means for ejecting said metals independently,said means including a valve having inlets for the admission of pressureand outlets connected to the ladles, and means for actuating the valve.

6. A die casting machine having a plurality of melting furnaces, eachhaving movable metal containers, a mold having a cavity, means forenlarging said cavity to take a plurality of layers of metal discharged5 from the ladles, the containers being adapted to be simultaneouslybrought into position to inject different fluid metals from the furnacesinto the cavity under pressure, and means for sealing the cavity.

7..A die casting machine having a plurality of melting furnaces, eachhaving movable metal containers with outlet orifices, and meansconnected to the containers to inject fluid metal into a-die mold underpressure.

8. A die casting machine having a pluralitypf melting furnaces, eachhaving movable metal containers with outlet orifices, means to forcemolten metal from the containers under pressure .at different times, a

separable die mold having a cavity, a core for successively enlargingthe cavity to receive successive layers of the molten metal, and meansfor sealing openings or joints in the die mold upon the formation of thefirst layer of metal andfor establishing a partial vacuum therein uponenlargement of the cavity to prevent oxidation of the first layer.

. 9. A die casting macgine having a plural- 3 ity of melting furnaces,each having movable metal containers with outlet orifices, means toforce molten metal from the containers under pressure, a separable diemold having a cavity, a core for enlarging the cavity to receive layersof the molten metal, and means for sealing openings or joints in the diemold after the formation of the first layer of metal, said mold havingan inlet orifice and a sprue lock for closing said orifice.

10. A die casting machine having a plu rality of melting furnaces, eachhaving movable metal containers with outlet orifices, means to forcemolten metal fromthe containers under pressure at different times, asepa 'able die mold having a cavity, a core for successively enlargingthe cavity to receive successive layers of the molten metal, and meansfor sealing openings or joints in the die mold upon the formation of thefirst layer of metal, said die mold having inlet orifices to receive themouth portions of the metal containers, a valvelcooperating with one ofsaid orifices to close the same after the injection of the first layerof fluid metal, and means for actuating said valve.

11. A die casting machine having a plurality of melting furnaces, eachhaving movable metalcontainers with outlet orifices, means to forcemolten metal from the containers under pressure at difierent times, aseparable die mold having a cavity, a core for enlarging the cavity toreceive layers of the molten metal, and means for sealing the die moldupon the formation of a layer of metal, said die mold adapted to receivethe metal from the outlet orifice of the metal containers, meanscooperating with at least one of said orifices to close the same aftertheinjection of said layer of fluid metal, means for ejecting thearticle produced in the cavity upon the separation'of the die mold andmeans for closing said die mold after ejection .of the article and priorto again receiving the molten metal.

12. A die casting'machine having a plurality of melting furnaces, eachhaving movable meta-l containers with outlet orifices, means to forcemolten metal from the containers under pressure at different times, aseparable die mold having a cavity, a core for successively enlargingthe cavity to receive successive layers of the molten metal, means forsealing openings or joints in the die mold upon the formation'of thefirst layer of metal, said die mold having inlet orifices to receive themouth portions of the metal containers, a valve cooperating with one ofsaid orifices to close the same after the injection of the first layerof fluid metal, and an oil groove forming member carried by the core.

13. A die casting machine having a plurality of melting furnaces,movable metal containers with outlet orifices near one end, means toforce molten metal therefrom under pressure, a separable die mold havinga cavity, a relatively movable core for sl'lccessively enlarging thecavity to receive successive layers of the molten metal, means forsealing openings or joints in the die mold upon the formation of thefirst layer of metal, said die mold having inlet orifices to receivetheoutlet orifices of the metal containers, a valve co-operating withone of said orifices to close the same after the injection of the firstlayer of fluid metal, an oil groove form ing member adjustably mountedin and carried by the corrnormally depressed so as not to project fromthe surface of the core, and means to project the same into the enlargedcavity when the core is moved, to form oil grooves when another layer ofmolten metal is injected into the cavity.

14. In a die casting machine, a mold having sections, at least one ofwhich is adapted to be moved relative to the other and having a cavityformed therebetween, means co-acting with said sections to enlarge orrestrict the cavity thereof for successively receiving molten metal toproduce a plurality of layers joined together by fusion, and oil grooveand hole forming members carried by the last-named means and one sectionrespec-- tively.

15. In a die casting machine, a mold having sections, at least one ofwhich is adapted to be moved relative to the other and having a cavityformed therebetwee-n, a movable core co-acting with said sections toenlarge or restrict the cavity thereof for successively receiving layersof molten metal to produce a plurality of layers joined together byfusion, and means for actuating the core.

16. In a die casting machine, a mold having sections, at least one ofwhich is adapted to be moved relative to the'othcr and having a cavityformed therebetween, means co-acting with said sections to enlarge orrestrict the cavity thereof for successively receiving molten metal toproduce aplurality of layers joined together by fusion, and means foractuating the last-named means. said means having lips or shouldersadapted to seal the cavity in the different positions of enlargement orreduction.

17. In a die casting machine, a mold having a cavity with inlet orificesconnlmnieating withcthe cavity, one section being movable toward andaway from the other, and a core having step portions engagingcorresponding openings in the sections and co-acting with the cavity toenlarge or reduce the same for receiving a plurality of molten metalmixtures for producing an article of a plurality of layers.

18. A die-casting machine havinga plurality of melting'furnaces, apivoted ladle in each furnace, each with an outlet orifice,

means connected to the opposite ends of the ladles to force molten metaltherefrom under 1 pressure, a separable die mold having a cavity, a corefor enlarging the cavity a plurality 5 of times to receive layers ofmolten metal,

means for sealing the joints or openings in the die mold after theformation of a layer of metal, said die mold having one or more in,-

let orifices to receive the outlet orifices of the w ladies, and meansfor closing said orifices at different times after injection of a layerof molten metal.

19. In a die-casting machine, a mold having sections at least one ofwhich is adapted to be moved relative to the other and having a cavityformed therebetween, a slidable core co-acting with said mold sectionsto enlarge or restrict the cavity thereof for successively receivinglayers of molten metal to produce a plurality of layers joined togetherby fusion, and means for actuating the core.

20. In a die-casting machine, a mold having sections, at least one ofwhich is adapted to be moved relative to the other, and having 5 acavity. formed therebetween, automatic means cooperating with saidsections to enlarge or restrict the cavity for successively receivinglayers of molten metal, means for expelling the air from within thecavity, and

means for actuating the first-named means to move it outwardly and tomove it in after the die is ejected.

21. The process of making a die cast article composed of a plurality ofmolten charges which consist in introducing the molten charge in aportion of a molding cavity, sealing said charge from atmosphere causinganother portion of the molding cavity to be presented to a chargingposition and then. introducing another molten charge in said otherportion of said cavity to join said charges together. 4

22. The process of die casting which consists in successively enlargingthe molding i5 cavity, injecting a plurality of molten metal mixturesinto the cavity and utilizing one of said mixtures to aid in sealing thecavity from I atmosphere before the inject-ion of the next mixturethereinto.

23. The method of die casting with a plurality of metals which consistsin successively enlarging a molding space, injecting a plurality ofmolten metal mixtures into said space successively as it is enlarged.expelling the air from within the space at the first inj ection andsealing said space against the entrance of air to provide a partialvacuum therein and prevent oxidation of the first injection uponenlargement of the space for receiving the next injection whereby thetwo metal injections may be joined together.

24. The process of die casting with a. plurality of metals whichconsists in filling a molding space with one molten metal under .25pressure, enlarging the space and then filling the enlargement withanother metal under, pressure and at the same time as said space isenlarged interposing a groove forming member in said cavity to cause agroove-to be formed in the metal forced into said enlargement.

.25. The process of die casting with a plurality of metals whichconsists in filling a molding cavity with one molten metal underpressure, enlargingthe cavity while the metal is still hot, expellingthe air from the cavity to prevent oxidation and then filling theenlargement of the cavity with another molten metal under pressure tocause the two metals to be joined together.

26. In a die casting machine, means for defining a molding cavity,receptacle means for molten metals, means for filling a portion of saidcavity with a charge of said molten metals, means for presenting anotherportion of said cavity to a charging position and means'for introducinganother of said molten metals in said other portion to join the moltenmetals in said cavity together.

27. In a die casting machine, means for defining a molding space,receptacle means for molten metal, means 'for injecting a plu rality ofcharges of said molten metal into said space and means for utilizing oneof said charges to aid in sealing the space from atmosphere before theinjection of the next charge therein.

28. In a die casting machine, means for defining a molding cavity,receptacle means for molten metal, means for filling the cavity with acharge of said molten metal, means for enlargingthe cavity and means forthen filling the enlargement of the cavity with another charge of moltenmetal to cause said two charges of metal to be joined together.

29. In a die casting machine, means for defining a molding cavity,receptacle means for molten metal, means for filling the cavity with acharge of said molten metal, means for enlarging the cavity, means forthen filling the enlargement of the cavity with another charge formolten metal to cause said two charges of metal to be joined together,

.' and means arrangedto be positioned in said cavity prior to theinjection of the second charge of molten-metal therein to cause a.groove to be formed in the second charge of metal as it is added to thefirst charge.

30. In a die casting machine, means for defining a molding cavity,receptacle means for molten metal, means \for filling the cavity with acharge of said molten metal, means comprising a movable corefor-enlarging the cavity and means for then filling the enlargement ofthe cavity withanother charge of molten metal to cause said two chargesof metal to be joined together.

31. In a die casting machine, means for definin a molding cavity,receptacle means for mo ten metal, means for filling the cavity with acharge of said molten metal, means comprising a movable core forenlarging the cavity and means for then filling the enlargement of thecavity with another charge of molten metal to cause said two charges ofmetal to be joined together, said core including a plurality ofdifferent sized portions adapted to be successively moved into thecavitv as the two charges are introduced therein.

32. .In a die casting machine, means for defining a molding cavity,receptacle means for molten metal, means for filling the cavity with acharge of said molten metal, means for enlarging the cavity and meansfor then filling the enlargement of the cavity With another charge ofmolten metal to cause said twocharges of metal to be joined together,

said enlarging means including a core having a plurality of differentmolding surfaces adapted to be successively introduced into the moldingcavity as the charges are injected in th 't a 8 can y AXEL AKERS.

